For a church to be constantly needing revival is the indication of much sin, for if it were sound before the Lord it would remain in the condition into which a revival would uplift its members. A church should be a camp of soldiers, not an hospital of invalids. But there is exceedingly much difference between what ought be and what is, and consequently many of God's people are in so sad a state that the very fittest prayer for them is for revival. Some Christians are, spiritually, but barely alive. When a man has been let down into a vat or into a well full of bad air, yea do not wonder when he is drawn up again that he is half-dead, and urgently requires to be revived. Some Christians—to their shame be it spoken!—descend into such worldly company, not upon such unhallowed principles, and become so carnal, that when they are drawn up by God's grace from their backsliding position they want reviving, and even need that their spiritual breath should as it were be breathed into their nostrils afresh by God's Spirit.
(C.H. Spurgeon, What Is a Revival?, From the December 1866 Sword and Trowel.)